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F@#&!!! My rear diff bushing is leaking!

31K views 39 replies 7 participants last post by  willy 
#1 ·
I'm so mad! :xZ!o: My 91K mile '03 has been absolutely problem free, not one problem, until now! I got a strange urge to look around under the car after I got home last night and I saw the infamous black liquid on the rear subframe!

Has anyone dealt with this issue? I absolutely can not spend the $1300 to have Nissan replace the rear subframe. It is my understanding that the bushing is not sold separately. Has anyone tried these:

SPL PRO SOLID DIFFERENTIAL BUSHINGS For NISSAN 350Z :: Rods, Arms, Bars :: Suspension :: 03-UP 350Z (Z33) :: Nissan :: Speed Alliance

I have no idea how to install these and it sounds like a daunting task to me. Do you have to drop the rear subframe to install this? Can I do this with common hand tools, a jack, and a couple stands?
 
#2 ·
by rear subframe, do you mean the whole differential? ...yes, you gotta drop the diff...
Here's the dealio, those stock bushing are soft so they can break (enter you). You have a couple options.
1. Those solid bushing you posted are awesome (so I hear, I have looked into them myself). They are a PITA to install (actually, mostly the old ones are a PITA to remove). IF you do it yourself, that is your cheapest and best performing option.
2. Just buy a whole new differential. You can get a whole vlsd pumpkin for 3-400$ All the will require is dropping the old pumpkin and putting the new one in its place.

Hope this helps a little...
 
#21 ·
#4 ·
I did this install with the car up on stands in my driveway. My pics of the tools i used are on the second last page of the thread. It's not that hard of an install at all, just be prepared to use alot of elbow grease.
 
#5 ·
I picked up a solid bushing, and I'm going to have it installed in the near future.

It's annoying me that Whiteline does a polyurethane replacement for the front diff bushings, but it the rear bushings that have a reputation for dying. I waited a year for them to release it when they told me they were working on it, and then it turns out its the wrong fucking components.

monk13 - where's your install thread?
 
#7 ·
monk13 - where's your install thread?
I didn't do an install thread as such, just added to the thread already there. If I had thought about it previously I would of made up a detailed one with millions of pics, but at the time I was pissed at the Mrs, and working on the car was a great escape.

Copy n pasted from the other thread:

Bumping this thread again. Spent the last couple of days doing some work on my Z, and these bushes were on the list. This thread was very helpful due to the fact that I knew I didnt have to press the bushes out. In hindsight however maybe I should of as they were a MAJOR PITA. I ended up ghetto rigging a press of sorts for the subframe bush, and belting the absolute crap out of the diff ones. The ghetto rigged press will probably come in handy for others so heres a couple pics.

Tools: Big G clamp and a 2 1/4" socket (had one handy but something else of similar size will do)


Socket placement


Clamp placement


Put the tool that comes with the kit on the rear side of the bushing and use it to center the clamp. Start winding the clamp in. IT WILL BE TIGHT, I got around this by putting a big spanner on the end of the clamp and using that as extra leverage. The socket is big enough to fit over the lip that the bush sits in, and will catch the bush as it falls out.

I really should of thought to of taken photos as I was doing it, but I got a little tunnel vision and wanted it done. Hopefully it gives the DIYers out there a few ideas.

Shane.
A socket that large wouldn't be easy to come by for most people unfortunately, Luckily both myself and my next door neighbor work on a mine site and seem to acquire the odd bit of massively over sized tooling...


I probably could of gotten away with not sanding, as the couple of ridges that were there were tiny, but I gave it a quick hit with a sandpaper attachment thingy for the old hand drill (READ: a couple seconds, as I didnt want to take much off the surface. see pic)



I also used the freezing the bush thing as well.
I have been running these bushes for around 20,000 km's now, and have had no drama's. Fire away with any questions desired. Or if anyone in Perth wants a set installed, and is willing to use their car as a tech-write up- demo car, let me know.

Shane
 
#6 ·
Scathing: The install is discussed in the thread that I posted above in post #3. Whiteline didn't make a urethane rear bushing for the diff because urethane will "cold flow" over time due to pressure. With the weight of the diff constantly on a urethane bushing, it would sag over time.

Willy: The bushing is press fit into the subframe and Nissan sells the bushing WITH the subframe...for $1300! So you have to drop the diff AND the subframe if you intend to use a press to remove the bushing the "proper" way.


I am going to get the bushing and give it a go sometime this month. I know that the bushing is awesome, but I am concerned about just getting the rear bushing and leaving the squishy front stock bushings in. Some people were discussing in that thread about how they thought that the stud could shear off the back of the diff due to torque put on the diff front squishy stock bushings allowing the diff to rotate. I know it's not likely but I really don't want solid bushings on the front too due to gear noise. Maybe I should get the Whiteline bushings for the front?
 
#8 ·
I'm so mad! :xZ!o: My 91K mile '03 has been absolutely problem free, not one problem, until now! I got a strange urge to look around under the car after I got home last night and I saw the infamous black liquid on the rear subframe!
Ok. I didn't know we had liquid in any of our bushings. I did have some dark gray fluid on my diff and rear subframe once (after a two-day event). But after asking around, I was told that I had boiled my differential fluid and it had "vented" all over the diff.

I changed the differential fluid the same weekend and all has been well since. (3 events and one two-day school).

My times have been consistent (on our test & tune track) before and after I noticed the issue, so if something else was at play, neither my times, nor my "seat dyno" have noticed.:dunno:
 
#9 ·
#10 ·
#16 ·
Just took a peek under the car, I see which bushing you're talking about in the subframe now... I was only thinking of the 2 smaller ones. I would guess that it would be much easier to remove that subframe, but the SPL bushings come with a driver to remove the bushing from the subframe, so it may be very possible to do it on the car. ...can't say either way with 100% certainty bc I haven't done it yet...
 
#17 ·
Now I'm paranoid, so I just went out and took some pics. I cleaned the diff cover before I changed the fluid so I just circled the area that was covered with fluid before..



Here are some remnants still there from a few months ago...


Stuff I never bothered to clean...


And some "splatter" way back, above the exhaust.



Now for the important question.

If this is the bushing, Should I not take it to ZdayZ like this? Can I wait and fix it this summer on the off-season, or should I make a B-line for the nearest shop?

Like I said, the car "feels" good, and still matches my best times, but I don't want to drive it if I am "hurting" it.
 
#22 ·
Now for the important question.

If this is the bushing, Should I not take it to ZdayZ like this? Can I wait and fix it this summer on the off-season, or should I make a B-line for the nearest shop?

Like I said, the car "feels" good, and still matches my best times, but I don't want to drive it if I am "hurting" it.
Well, here is mine:



It's pretty obvious what's going on with mine. Yours, on the other hand isn't so easy to tell. I have read that some people have had these pop like a pimple (even after they've been leaking) when they were trying to remove it. Maybe something similar happened here. During one of your track days, maybe a violent motion of the diff caused it to explode everywhere. It isn't a huge deal to replace it right away. It will cause the handling to be slightly unpredictable, cause wheel hop, and speed up wear on the tranny output gears. I wouldn't be worried about it until the off season. On the other hand, I'd be willing to bet that replacing all three diff bushings would make you noticeably faster.
 
#18 ·
How long ago was it??
 
#20 ·
well mine hasn't torn so I can't say for sure, but the consistency of that fluid and the fact that it looks like it originated near the bushing seems suspect... The OP can probably give a little better insight...
 
#23 ·
Ouch.

The only 'problem' I see is that the ride will be affected (as in comfort) with the solid diff bushings. Maybe I'm mistaking it for another part, but I read that those solid bushings make the car a rougher ride.
 
#26 ·
I have not noticed any difference in comfort levels at all. The only real noticeable change is the extra noise, due to having no rubber to absorb the sound. cruising at anywhere above 80km/h, is about the only time I really hear it, and even then it's not loud enough to get annoying.
 
#25 ·
All this talk makes me want to go under the car and look around. I'll do that on my next oil change before Zdayz.
 
#28 ·
Yep, ride quality shouldn't be changed. There are still rubber bushings on the subframe. There is more gear noise from the diff.
 
#29 · (Edited)
I ordered the SPL kit today and hope to install the rear bushing Wednesday.

If I can find a shop to "press" the other two bushings onto my pumpkin, I will have those done too. Otherwise, I will just do the rear bushing.

I have never done anything this difficult mechanically, but I have found a few how-to's with lots of tips and pics.
 
#30 ·
I ordered the SPL kit today and hope to install the rear bushing Wednesday.

If I can find a shop to "press" the other two bushings onto my pumpkin, I will have those done too. Otherwise, I will just do the rear bushing.

I have never done anything this difficult mechanically, but I have found a few how-to's with lots of tips and picks.
...I don't think it should be that hard, the most difficult part will probably be getting the old one out, if I had to guess. Just be careful lowering the pumpkin down, it's HEAVY! ...might have to move the exhaust out of the way too....

Post up pics / how to afterwards :cheers:
 
#31 ·
Getting the other bushes in is easy. Getting them out is the hard bit, but it is possible.

Basic steps to this install.

Get the car up in the air. Use axle stands etc. Do it safely.
Remove exhaust. I removed the Y-pipe as well.
Remove the sensors. Be gentle they are apparently pretty easy to damage. I got some race tape and stuck them to the floor pan.
Remove nuts and bolts from tailshaft and driveshafts. Be careful with the tailshaft and don't let it fall heavily onto the brace under the car.
Remove the nut from the subframe bush.
Support the pumpkin on a trolley jack.
Undo the 2 remaining bolts and lower the pumpkin down.
Remove subframe bush with my ghetto press (in pics earlier)
press new bush in with ghetto press. If you put the bush in the freezer the night before, it will shrink slightly and help it go in.
Belt the **** out of the bushes in the pumpkin until they come out.
Belt the new bushes in. hit the install tool supplied not the bushes themselves.
Install pumpkin, shafts, senors and exhaust. I always use a drop of Loctite on tailshaft bolts and driveshaft bolts.
Go for a lap around the block, and then check the tension on all the nuts n bolts.
Drink beer. :beer:
 
#33 ·
haha +1 ... I always check under there, but I went out and checked again the other day just in case!
 
#35 ·
...i don't think it is that well-known of a problem... I mean, I didn't know about it until I started researching which LSD to get, and if Gus even just got worried about it, I don't think it was much fault of your own... lucky this thread came up now though! :cheers:
 
#38 ·
I think if you pack them in rice and leave them in the freezer overnight they'll slip right in... Can you post how you get the old ones out though??
 
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